The field of the invention relates to X-ray imaging systems and more particularly to cargo inspections systems.
Portable X-ray inspection systems for trucks are generally known. Such systems are typically used to perform non-invasive inspection of trucks for contraband (e.g., explosives, drugs, etc.). Often an X-ray beam is directed through the truck to a set of detectors on an opposing side.
As the radiation of the X-ray beam passes through the truck, the contents of the truck attenuate the beam based upon the density of the contents. Based upon the attenuation, an image may be formed of the truck""s contents. By comparing a truck""s manifest with the X-ray image, law-enforcement personnel may make a determination of whether on not they have probable cause to believe that any laws have been broken.
One form of such devices is constructed in the form of a gantry with an X-ray source on one side and an X-ray detector on an opposing side. A hoist is usually provided to raise and lower the X-ray source or detector in unison. Such devices may be rubber tire or rail mounted.
In order for the gantry to span a semi-tractor trailer, the gantry must necessarily be quite high and quite wide (e.g., four or more feet higher and wider than the semi-tractor trailer). Because of the height and width of gantry-type inspection systems, they are generally not regarded as being very mobile and generally require special permits for highway travel.
Other truck inspection devices have used X-ray sources mounted to a truck-bed and a moveable boom to position a detector on an opposing side of the truck to be inspected. When not in use, the moveable boom could be folded and stored in a position directly above a centerline of the truck.
Because of the relatively stationary location of the X-ray source on the truck bed, such systems have difficulty effectively inspecting locations on trucks that are close to the road or on the top of the truck adjacent the X-ray source. As a result, the X-ray detectors are often exceptionally large to cover peripheral areas which adds to the overall size and expense of such systems. In addition, because of the difficulty in scanning peripheral areas, such systems are not readily adaptable to a variety of different cargo-handling enclosures.
While existing portable X-ray inspection systems have been effective, their size has impeded their use. Because of the importance of cargo inspection, a need exists for a X-ray inspection system that is mobile and adaptable to a variety of applications.